Abstract
Purpose :
Ahmed glaucoma valve (AGV) implant placement in conjunction with pan retinal photocoagulation (PRP) is frequently used in the management of neovascular glaucoma (NVG). AGV can be placed either in the pars plana (PP) or anterior chamber (AC). PRP can be performed in the office or intraoperatively with pars plana vitrectomy (PPV). This study compared the outcomes between PP AGV with PPV and endolaser (EL) versus AC AGV with in office PRP.
Methods :
This is a retrospective study that investigated all AGV implants in patients with NVG at the University of Rochester Medical Center between 1/2010 and 1/2020. We performed a chart review to compare the outcomes between patients who underwent AGV in the setting of NVG: group 1 (PP AGV + PPV/EL) and group 2 (AC AGV + PRP). The outcome measures were intraocular pressure (IOP, mmHg) and visual acuity (VA, LogMar). The change in IOP and VA between these two groups, adjusted for preoperative lens status, was compared at 6-month and 1-year intervals using the analysis of variance.
Results :
Both groups consisted of 15 subject eyes at baseline. Eleven (73%) eyes were pseudophakic in group 1 while 3 (20%) eyes were pseudophakic in group 2. The mean baseline IOP (38.6 ± 6.6 vs. 43.0 ± 8.9 mmHg) and VA (1.4 ± 0.7 vs. 1.3 ± 0.8 LogMar) were similar between groups 1 and 2. The adjusted change in IOP between groups 1 and 2 was not statistically significant at 6 months (-20.5 ± 6.1 vs. -25.6 ± 9.5 mmHg, p = 0.11) and 1 year (-23.8 ± 10.3 vs. -27.9 ± 11.0 mmHg, p = 0.38). The adjusted change in VA between groups 1 and 2 was also not statistically significant at 6 months (-0.04 ± 0.60 vs. -0.28 ± 0.66 LogMar, p = 0.32) and 1 year (0.12 ± 0.68 vs. -0.40 ± 0.72 LogMar, p = 0.10). In group 1, 2 eyes had foveal macular edema, 1 developed a retinal detachment, and 1 had rapid cataract progression. In group 2, 1 eye required a tube revision, 1 required further transscleral laser therapy, and 2 had cataract surgery.
Conclusions :
PP AGV + PPV/EL and AC AGV + PRP were both effective in lowering IOP, and there was no significant difference between them. There was a trend toward better VA at 1 year in group 2, but this was not statistically significant. A prospective study and larger sample size is needed to address this question and further evaluate the outcomes of both treatment modalities.
This is a 2021 ARVO Annual Meeting abstract.